I purchased this for my husband, who uses a wheelchair and sometimes, a walker. He wanted a cup holder to attach to his equipment, that would hold a cup of coffee or tea OR a glass of water OR a soda can. The circumference of this device will only hold a soda can. He also uses it to hold keys, gadgets, and small things, when he is using the walker or wheelchair. I would recommend, but just not for coffee cups or mugs.